Bleeding New System

[fidom]

I have installed a solid fuel vented system with 2 pipe radiator circuit plumbed in 15mm. There are 7 rads but I can only get 4 of them to bleed successfully. I get some air out of the others but no water. It is a single storey property but the problem rads are reached by pipes which run above the entrance door. The pump is on the return and I think that might be the problem. I realise the pump can't pump air but it perhaps needs the pump pressure to raise water the 2 metres or so to get over the doorway.
Is there a standard procedure for such cases to introduce water locally direct into a rad whilst avoiding airlocks elsewhere in the pipework? There are no TRVs. The house is in Croatia. One of the problem rads is a tall towel rail radiator so that seems like the obvious choice for a secondary filling point.

 

[stem]

The pump can suck air into the system if there is an opening that will allow it to enter. This is why the pump should not be running when you are bleeding the radiators. So whether it is on the flow or return won't make any difference during the bleeding exercise.

You could have a blocked feed pipe so there isn't enough pressure to force the air out of the radiators.

 

[polesapart]

Run the pipes under the door. Or bleeding fit vent nipples on high points.

 

[PullerGas]

Blast the system with mains pressure water. Connect a hose at the DOC & get someone to keep an eye on the water level in the F&E tank.

 

[fidom]

Blast the system with mains pressure water. Connect a hose at the DOC & get someone to keep an eye on the water level in the F&E tank.

Yes, I was thinking along those lines but I'm only using water for testing purposes. I will be filling the system with Fernox Solar antifreeze when I'm satisfied it is working correctly and no leaks. This product is not a concentrate so I need to drain off all the water before I use it. Winters can go down to -20C here so I want more frost protection than I would for a UK system.